Does a bone bruise mean I tore my ACL?

The ACL pattern

When the ACL tears during a pivot or awkward landing, the shin bone slides forward and rotates. For a moment the outer part of the thigh bone strikes the back of the outer shin bone, leaving matching bruises on both. Radiologists sometimes call these kissing contusions.

This pattern is seen in a large proportion of acute ACL tears and may also point to injury of the outer meniscus or its root, which are checked on the same scan.

Other causes of bone bruising

• Kneecap dislocation: bruising on the inner side of the kneecap and the outer thigh bone
• Direct blow: a single bruise where the knee hit the ground, a dashboard or another player
• Hyperextension: bruising at the front of both the thigh and shin bones, sometimes with PCL or posterolateral corner injury
• Valgus or sideways force: bruising on the outer side with an MCL injury on the inner side
• No clear injury: may be a stress reaction or another bone condition, especially in older adults

How the ACL is actually assessed

The MRI shows the ligament itself, but the examination matters just as much. Tests such as the Lachman and pivot shift check how the knee moves. A bone bruise is a supporting sign; the decision is based on the ligament's appearance on MRI, how the knee feels to examine, and whether it gives way in daily life or sport.

If the ACL is intact, the bruise is usually treated on its own with protected activity and rehabilitation.

Next steps in Doha

If you injured your knee playing football, padel or basketball and the MRI shows a bone bruise, bring the images to an appointment. At Aman Hospital Dr. Gelber reviews the scan, examines the ligaments and menisci, and explains whether you have an isolated bruise or a combined injury, and what treatment that means.